Best Way to Remove a Rounded Screw

panthro · 19 Sep 2006 at 20:06

Basically....help!

The screw on my engine cover is rounded and I need to remove it to get to the brake fluid reservoir. I dont have a dremel but I have a drill and plenty of drill bits. I have never removed a rounded screw and dont want to "screw" (sorry) it up. I dont need the engine cover as its just a cheap Renault one, but I would prefer not to break it! Thanks.

JohnnyG · 19 Sep 2006 at 20:07

Probably get more help in motors, but I'd try cutting a new slot with a hacksaw

AmaTeX · 19 Sep 2006 at 20:09

JohnnyG said:
Probably get more help in motors, but I'd try cutting a new slot with a hacksaw

And then put plenty of easing fluid on before you try to remove it again

shimy182 · 19 Sep 2006 at 20:09

either get a dremel like thing and put a line on the head of the screw, back up plan will be to drill it out

panthro · 19 Sep 2006 at 20:10

AmaTeX said:
And then put plenty of easing fluid on before you try to remove it again

I did (WD40), but it was fairly rounded in the first place. Didnt help.

Jez · 19 Sep 2006 at 20:11

May sound obvious, but can you not get to the screw in such a way as you could just turn it with some molegrips?

TaKeN · 19 Sep 2006 at 20:12

Impact tool ?

You hit it with a hammer, and it twists at the same time

panthro · 19 Sep 2006 at 20:13

Jez said:
May sound obvious, but can you not get to the screw in such a way as you could just turn it with some molegrips?

No unfortunately not

-westy- · 19 Sep 2006 at 20:14

as above, just get a hacksaw and cut a new slot in the top if it. unless its sitting flush...in which case just drill it out

Jez · 19 Sep 2006 at 20:15

panthro said:
No unfortunately not

I was just thinking that if you were able to get to it to cut a slot as others have suggested, then you would likely have enough access to simply molegrip it out.

Might be a matter of breaking the engine cover or drilling it then mate :/

panthro · 19 Sep 2006 at 20:15

-westy- said:
as above, just get a hacksaw and cut a new slot in the top if it. unless its sitting flush...in which case just drill it out

what would happen when I drill it out? If the drill bit is big enough I presume it will just fall apart?

panthro · 19 Sep 2006 at 20:16

Jez said:
I was just thinking that if you were able to get to it to cut a slot as others have suggested, then you would likely have enough access to simply molegrip it out.

Might be a matter of breaking the engine cover or drilling it then mate :/

Will try the mole grip idea but there is literally 2mm max of the head showing. If not then I will try the hacksaw option. If not, then the drill will have to come out.

KennyBhoy · 19 Sep 2006 at 20:17

panthro said:
what would happen when I drill it out? If the drill bit is big enough I presume it will just fall apart?

In theory yes, it should just crumble....The trick is not to damage the thread though that your new screw will go into

Jez · 19 Sep 2006 at 20:17

Take out another one the same, to see how big the shaft of the screw is. Then pick a bit that will be slightly smaller than the actual shaft of the screw (not the threads). Then drill down the knackered screw carefully.

Alternatively go for a bigger bit and drill out the whole lot if the screw is non critical

shimy182 · 19 Sep 2006 at 20:18

or.. carve the sides off and use a wrench to twist it out with a plier

Scuzi · 19 Sep 2006 at 20:20

You could weld a nut to it and take it out using a socket or a spanner.

Bear · 19 Sep 2006 at 20:20

Depending if you can actualy get to it, I normally use a pair of side cutters. Just grip the screw head and twist, it nearly always works unless the screw is really corroded in.

panthro · 19 Sep 2006 at 20:33

Bear said:
Depending if you can actualy get to it, I normally use a pair of side cutters. Just grip the screw head and twist, it nearly always works unless the screw is really corroded in.

Side cutters?

My dad has pretty much every tool (except a dremel!) and I have found some screw extractors (drill bits) so Im just charging the drill up now.

Malachy · 19 Sep 2006 at 20:44

panthro said:
Side cutters?

there ya go

Treefrog · 19 Sep 2006 at 20:45

Choose a drill bit that's the same size or slightly bigger than the shaft of the bolt and drill the head off. Then take the cover off and lock your molegrips onto the shaft as tight as you can and unscrew it. Then replace all the bolts with Allen bolts for next time.